package org.openfantasia.musica.instruments.jmusic;

import jm.audio.AudioObject;
import jm.audio.Instrument;
import jm.audio.io.SampleOut;
import jm.audio.synth.*;

/**
 * A triangle waveform instrument implementation
 * which iincludes a low pass filter that is swept by
 * an envelope.
 *
 * @author Andrew Brown
 */

public final class LPFilterEnvInst extends Instrument {
	//----------------------------------------------
	// Attributes
	//----------------------------------------------

	private int sampleRate;

	private int filterCutoff;

	private int channels;

	//----------------------------------------------
	// Constructor
	//----------------------------------------------


	/**
	 * Basic default constructor
	 *
	 * @param sampleRate
	 */
	public LPFilterEnvInst(int sampleRate) {
		this(sampleRate, (int) (sampleRate * 0.02), 1);
	}


	/**
	 * Constructor that sets sample rate and filter cutoff centre frequency
	 *
	 * @param sampleRate	 The number of samples per second (quality)
	 * @param filterCutoff The frequency above which overtones are cut
	 */
	public LPFilterEnvInst(int sampleRate, int filterCutoff) {
		this(sampleRate, filterCutoff, 1);
	}


	/**
	 * Constructor that sets all attributes
	 *
	 * @param sampleRate	 The number of samples per second (quality)
	 * @param filterCutoff The frequency above which overtones are cut
	 * @param channels		 1 for Mono or 2 for Stereo
	 */
	public LPFilterEnvInst(int sampleRate, int filterCutoff, int channels) {
		this.sampleRate = sampleRate;
		this.filterCutoff = filterCutoff;
		this.channels = channels;
	}


	/**
	 * Initialisation method used to build the objects that
	 * this instrument will use and specify thier interconnections.
	 */
	public void createChain() {
		// filter envelope
		Envelope filtEnv = new Envelope(this, this.sampleRate, this.channels,
				new double[]{0.0, 0.0, 0.2, (this.sampleRate * 0.4), 0.4, 0.0, 0.6, (this.sampleRate * 0.3), 1.0,
						(this.filterCutoff * 0.1)});
		// oscilator
		Oscillator osc = new Oscillator(this, Oscillator.TRIANGLE_WAVE, this.sampleRate, this.channels);
		// filter
		Filter filt = new Filter(new AudioObject[]{osc, filtEnv}, this.filterCutoff, Filter.LOW_PASS);
		Envelope env = new Envelope(filt,
				new double[]{0.0, 0.0, 0.05, 1.0, 1.0, 0.0});
		Volume vol = new Volume(env);
		StereoPan pan = new StereoPan(vol);
		SampleOut sout = new SampleOut(pan);
	}
}

